The Java code for this recipe is located in the org.camelcookbook.transformation.json package. The Spring XML files are located under src/main/resources/META-INF/spring and prefixed with json.

To use Camel's JSON Component, you need to add a dependency element for the camel-xstream library, which provides an implementation for the JSON Data Format using the XStream library.

Add the following to the dependencies section of your Maven POM:

<dependency>
  <groupId>org.apache.camel</groupId>
  <artifactId>camel-xstream</artifactId>
  <version>${camel-version}</version>
</dependency>

Reference the Data Format within your route, choosing the marshal (Java to JSON), or unmarshal (JSON to Java) statement, as appropriate:

In the XML DSL, this is written as follows:

<route>
  <from uri="direct:marshal"/>
  <marshal>
    <json/>
  </marshal>
  <to uri="mock:marshalResult"/>
</route>

In the Java DSL, this same route is expressed as:

from("direct:marshal")
  .marshal().json()
  .to("mock:marshalResult");

Using Camel JSON simplifies translating your data between JSON and Java. This is convenient when you are dealing with REST endpoints and need Java processors in Camel to do custom message processing later on in the route.

Camel JSON provides a wrapper around the JSON libraries for instantiating the Java binding for the JSON data, eliminating more boilerplate code from your integration flows.

Camel JSON works with the XStream library by default, and can be configured to use other JSON libraries, such as Jackson or GSon. These other libraries provide additional features, more customization, and more flexibility that can be leveraged by Camel. To use them, include their respective Camel components, for example, camel-jackson, and specify the library within the json element:

<dataFormats>
  <json id="myJson" library="Jackson"/>
</dataFormats>